The invention pertains to a process for the thermal treatment of materials which contain vaporizable substances, in order to form gases, vapors, condensates, and solids for the purpose of processing and/or disposal. The treatment occurs under negative pressure, without the introduction of oxygen, and under decreasing pressures and increasing temperatures.
The process in question pertains to the treatment of materials containing organic components such as hydrocarbons, including halogenated hydrocarbons, and/or inorganic components such as metals, filter dust, acids, lyes, etc. These materials include not only waste and garbage, but also valuable materials such as laminates of metal and elastomers such as old tires, steering wheels, packings of elastomeric materials, gaskets, contaminated flooring materials, etc.
The process can be used to convert the selected materials completely into harmless solids (ash) and gases. Depending on how the process is set up, it can also be used to recover at least a portion of the components as valuable substances in the form of, for example, condensed hydrocarbons and/or carbon, which can be sent on for some type of other useful purpose. Of course, it is also possible to use the condensates and/or the carbon as fuels within the scope of the overall disposal plan.
DE 41 12 593 discloses exposing waste materials with organic components to a single-stage pyrolysis process in the presence of oxygen. This leads to the recovery of metals, vitrified building materials, and energy. It is not possible, however, to recover fractionated distillates. On the contrary, all of the pyrolysis products obtained in the form of gases and vapors are sent to a high-temperature gasification stage and incinerated in their entirety. With the exception of metals, no valuable materials are recovered.
DE 44 18 562 discloses a single-stage thermal process in which valuable materials in the form of combustible gases and distillates and embrittled conversion products are recovered. The process is operated exclusively in a discontinuous manner; in the single treatment chamber, the pressure is reduced and the temperature raised in a temporal sequence. As a result, a mixture of distillates which can then be separated into its individual components is obtained, although this involves a complicated process of fractional distillation. The use of the treatment chamber is not efficient, because the selected substances initially occupy a large volume and gradually lose volume only during the course of the thermal process.